Robotic Tactile Sensor Incorporating Silicon Planar Technology: A Piezoelectric Polyvinylidene Fluoride Film, and ON-Chip Signal Processing.

摘要

This research effort pursued the design, fabrication, and test of a robotic tactile sensor. The VLSI integrated circuit (IC) portion of the sensor included a 7 x 7 array of metal electrodes which were individually connected to identical MOSFET amplifiers. A 25 micrometers thick patch (6 mm x 6 mm) of piezoelectric polyvinylidene fluoride (PVDF) film was attached to the array with a non-conductive adhesive, thereby creating an array of taxels. Charge, generated by the PVDF film, was detected by the amplifiers. The outputs of these amplifiers were connected to onchip signal circuitry designed to produce a single stream of serial data. A problem with the signal processing circuit circumvented the proper operation of the entire IC. Therefore, an external multiplexer was used to analyze the performance of a 3 x 3 array of taxels located in the center of the 7 x 7 array. The key factor affecting the performance of the sensor was establishing a uniform initial charge state condition across the 3 x 3 array. Schemes for manifesting this condition were examined as well as characterization of taxel load response. A fundamental image recognition process successfully recognized an applied shape by comparing the pre-load, load, and post-load multiplexed output of the array.